Multidimensional Scaling of the Cognitive Assessment System‐Second Edition: Implications for the Structural Validity of PASS Theory and Its Application in School Psychology

ABSTRACT This study applied multidimensional scaling (MDS) to the Cognitive Assessment System‐Second Edition (CAS2) to investigate the structural validity of PASS theory (Planning, Attention, Simultaneous, Successive) across two age groups (5−7, 8−18 years) in the normative sample ( N = 1342). MDS is a statistical technique that creates a visual map showing similarities and differences between objects in a visual array of the distances between them. Accordingly, MDS offered a spatial representation of subtest relationships, revealing near‐perfect model fit for both groups. Results indicated some clustering of Planning and Attention measures, partially supporting prior findings that these constructs may be psychometrically fused. Expressive Attention displayed atypical spatial placement from ages 8 to 18, suggesting factorial complexity beyond those linkages. A radex‐like structure emerged, with cognitively complex tasks centrally located and more differentiated configurations observed in older participants, consistent with the developmental mutualism hypothesis. Findings highlight persistent challenges in cleanly separating PASS processes, with implications for CAS2 interpretation and intervention design. MDS proved a valuable complement to factor analysis, offering nuanced insights into test dimensionality and the ongoing debate over the validity of PASS theory.